Non-contact charging module and reception-side and transmission-side non-contact charging apparatuses using the same

ABSTRACT

It is an object to provide a non-contact charging module that uses a magnet included in a counterpart-side non-contact charging module or does not use the magnet when aligning with the counterpart-side non-contact charging module is performed. An L value of a coil that is provided in the non-contact charging module is not changed. This non-contact charging module includes a planar coil portion where electrical lines are wound and a magnetic sheet that places a coil surface of the planar coil portion and faces the coil surface of the planar coil portion, and in the magnetic sheet, a hole portion is provided at the position corresponding to a hollow portion of the planar coil portion.

REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/355,865, filed on Jan. 23, 2012, which claims priority from JapanesePatent Application Nos. 2011-013617, filed Jan. 26, 2011, 2011-131946,filed Jun. 14, 2011, 2011-131947 filed Jun. 14, 2011 and 2011-131948,filed Jun. 14, 2011, the entire contents of which are incorporatedherein by reference.

TECHNICAL FIELD

The present invention relates to a non-contact charging module that hasa planar coil portion made of spiral electrical lines and a magneticsheet and a reception-side and transmission-side non-contact chargingapparatuses using the same.

BACKGROUND ART

In recent years, apparatuses that charge a body apparatus in anon-contact type using a charger are widely used. In the apparatuses, atransmission-side non-contact charging module is disposed on the side ofthe charger, a reception-side non-contact charging module is disposed onthe side of the body apparatus, and electromagnetic induction isgenerated between the modules to supply power from the side of thecharger to the side of the body apparatus. In addition, it is suggestedto apply a portable terminal apparatus as the body apparatus.

It is demanded to decrease the thickness and the size of the bodyapparatus or the charger of this portable terminal apparatus. In orderto meet the demand, it is considered to include a planar coil portionfunctioning as the transmission-side non-contact charging module or thereception-side non-contact charging module, and a magnetic sheet (referto Patent Literature 1).

CITATION LIST Patent Literature

PTL 1

Japanese Patent Application Laid-Open No. 2006-42519

SUMMARY OF INVENTION Technical Problem

In this type of non-contact charging module, the position of aprimary-side non-contact charging module (transmission-side non-contactcharging module) and the position of a secondary-side non-contactcharging module (reception-side non-contact charging module) need to beaccurately aligned. This is to efficiently perform the electromagneticinduction to transmit power.

A method using a magnet is known as one method that accurately alignsthe position of the primary-side non-contact charging module(transmission-side non-contact charging module) and the position of thesecondary-side non-contact charging module (reception-side non-contactcharging module). In this method, the other non-contact charging moduleis aligned by using the magnetic included in one non-contact chargingmodule. This method is a method in which the magnet is mounted to atleast one of the primary-side non-contact charging module and thesecondary-side non-contact charging module, the magnets of both sides orone magnet and the other magnetic sheet attract each other, andtherefore aligning is performed.

A method that performs aligning without using the magnet is known asanother method that accurately aligns the position of the primary-sidenon-contact charging module and the position of the secondary-sidenon-contact charging module.

For example, this is a method in which a convex portion is formed in acharging surface of a charger mounted with the primary-side non-contactcharging module, a concave portion is formed in an electronic apparatusmounted with the secondary-side non-contact charging module, the convexportion are fitted in the concave portion, and compulsory aligning ofthe primary-side non-contact charging module and the secondary-sidenon-contact charging module is physically (geometrically) performed.This is a method in which the primary-side non-contact charging moduledetects the position of a coil of the secondary-side non-contactcharging module in order to automatically move the position of the coilof the primary-side non-contact charging module to the position of acoil of the secondary-side non-contact charging module. This is a methodin which a plurality of coils are provided in the charger such that aportable apparatus is chargeable in all places of a charging surface ofthe charger.

However, in the case where the magnet is used in aligning of theprimary-side non-contact charging module and the secondary-sidenon-contact charging module and the case where the magnet is not used,an L value of the coil that is provided in each non-contact chargingmodule significantly changes. In the electromagnetic induction to supplypower, the resonance frequency is determined using the L value of thecoil that is provided in each non-contact charging module.

For this reason, in the case where the magnet is used in aligning of theprimary-side non-contact charging module and the secondary-sidenon-contact charging module and the case where the magnets is not used,there is a problem that it is difficult to commonly use the non-contactcharging module.

Therefore, in view of the above problems, it is an object of the presentinvention to provide a non-contact charging module that can suppress achange in an L value of a coil provided in the non-contact chargingmodule in both of the case where a magnet included in the othernon-contact charging module is used when a primary-side non-contactcharging module and a secondary-side non-contact charging module arealigned and the case where the magnet is not used, and can be used inboth of the case where the magnet is used and the case where the magnetis not used. Further, it is an object of the present invention toprovide reception-side and transmission-side non-contact chargingapparatuses using the same.

Solution to Problem

In order to solve the above problems, the present invention provides anon-contact charging module that has a case where using a magnetincluded in a counterpart-side non-contact charging module or a casewhere not using the magnet, when aligning with the counterpart-sidenon-contact charging module is performed. The non-contact chargingmodule includes a planar coil portion where electrical lines are woundand a magnetic sheet that places a coil surface of the planar coilportion and faces the coil surface of the planar coil portion. In themagnetic sheet, a hole portion is provided at the position correspondingto a hollow portion of the planar coil portion.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the present invention, an L value of a coil that isprovided in the non-contact charging module is not changed in both ofthe case where the magnet included in the other non-contact chargingmodule (the primary-side non-contact charging module or thesecondary-side non-contact charging module) is used and the case wherethe magnet is not used, when the primary-side non-contact chargingmodule and the secondary-side non-contact charging module are aligned,so that it is possible to provide a non-contact charging module that canperform superior aligning and power transmission in both of the casewhere the magnet is used and the case where the magnet is not used.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a block diagram illustrating a non-contact power transmittingapparatus according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating the configuration of a non-contactcharger according to the embodiment of the present invention;

FIG. 3 is a diagram illustrating a primary-side non-contact chargingmodule according to the embodiment of the present invention;

FIGS. 4A, 4B, 4C and 4D are a detailed diagram illustrating theprimary-side non-contact charging module according to the embodiment ofthe present invention;

FIG. 5 is a diagram illustrating the configuration of a portableterminal apparatus according to the embodiment of the present invention;

FIG. 6 is a diagram illustrating a secondary-side non-contact chargingmodule according to the embodiment of the present invention;

FIGS. 7A, 7B, 7C and 7D are a detailed diagram illustrating thesecondary-side non-contact charging module according to the embodimentof the present invention;

FIGS. 8A, 8B, 8C, 8D and 8E are a conceptual diagram of a magnetic sheetof a non-contact charging module according to the embodiment of thepresent invention;

FIG. 9 is a diagram illustrating a relation of an L value of a coil ofthe non-contact charging module and the thickness of a center portion inthe case where a magnet is used and the case where the magnet is notused in aligning in the other non-contact charging module according tothe embodiment of the present invention; and

FIGS. 10A and 10B are a top view of a non-contact charging moduleaccording to the present invention where a coil is wound in arectangular shape or a circular shape.

DESCRIPTION OF EMBODIMENTS

In the invention according to claim 1, a non-contact charging modulethat uses a magnet included in a counterpart-side non-contact chargingmodule or does not use the magnet when aligning with thecounterpart-side non-contact charging module is performed is provided.The non-contact charging module includes a planar coil portion whereelectrical lines are wound and a magnetic sheet that places a coilsurface of the planar coil portion and faces the coil surface of theplanar coil portion. In the magnetic sheet, a hole portion is providedat the position corresponding to a hollow portion of the planar coilportion. Thereby, an L value of a coil that is provided in thenon-contact charging module is not changed in both of the case where themagnet included in the counterpart-side non-contact charging module isused and the case where the magnet is not used, when the primary-sidenon-contact charging module and the secondary-side non-contact chargingmodule are aligned. Therefore, a non-contact charging module that can beefficiently used in both of the case where the magnet is used and thecase where the magnet is not used can be obtained.

In the invention according to claim 2, the hole portion is athrough-hole. Thereby, an influence of the magnet that is used inaligning can be suppressed to a minimum.

In the invention according to claim 3, the depth of the hole portion is40 to 60% of the thickness of the magnetic sheet. Thereby, the L valuesof the coil in the case where the magnet is used in aligning and thecase where the magnet is not used in aligning can be set to be similarto each other and an aligning effect of the magnet can be sufficientlyobtained.

In the invention according to claim 4, the electrical lines of theplanar coil portion are wound in a circular shape. Thereby, the magneticflux can be equally generated and power transmission can be stablyperformed.

In the invention according to claim 5, a shape of a top surface of thehole portion is the same as a shape of the hollow portion of the planarcoil portion. Thereby, the magnet and the center portion of the magneticsheet attract with a good balance and the centers thereof can beprecisely aligned.

In the invention according to claim 6, all of ends of the hole portionhave the same distance from ends of the hollow portion of the planarcoil portion. Thereby, the magnet and the center portion of the magneticsheet attract with a good balance and the centers thereof can beprecisely aligned.

In the invention according to claim 7, the hole portion is formed to bebigger than the magnet. Thereby, an influence of the magnet can besuppressed with a good balance.

In the invention according to claim 8, the center of the hole portion ismatched with the center of a center portion of the planar coil portion.Thereby, the magnet and the center portion of the magnetic sheet attractwith a good balance and the centers thereof can be precisely aligned.

In the invention according to claim 9, the electrical lines of theplanar coil portion are wound in a rectangular shape. Thereby, powertransmission can be efficiently performed.

Embodiment

Now, an embodiment of the present invention will be described in detailwith reference to the accompanying drawings.

FIG. 1 is a block diagram illustrating a non-contact power transmittingapparatus according to an embodiment of the present invention.

The non-contact power transmitting apparatus includes primary-sidenon-contact charging module 1 (transmission-side non-contact chargingmodule) and secondary-side non-contact charging module 2 (reception-sidenon-contact charging module) and transmits power from primary-sidenon-contact charging module 1 to secondary-side non-contact chargingmodule 2 using an electromagnetic induction action. The non-contactpower transmitting apparatus is used in transmitting power of about 5 Wor less. The frequency of power transmission is about 110 to 205 kHz.

Primary-side non-contact charging module 1 is mounted to a charger andsecondary-side non-contact charging module 2 is mounted to, for example,a mobile phone, a digital camera, and a PC. Primary-side non-contactcharging module 1 includes primary-side coil 11 a, magnetic sheet 3,resonance capacitor (not illustrated), and power input section 5. Powerinput section 5 is connected to commercial power supply 300 functioningas an external power supply, receives power of about 100 to 240 V,converts the power into a predetermined current (direct current 12 V, 1A), and supplies the predetermined current to primary-side coil 11 a.Primary-side coil 11 a generates a magnetic field according to the shapethereof, the winding number thereof, and the supplied current. Theresonance capacitor is connected to primary-side coil 11 a anddetermines the resonance frequency of the magnetic field generated fromprimary-side coil 11 a according to a relation with primary-side coil 11a. The electromagnetic induction action from primary-side non-contactcharging module 1 to secondary-side non-contact charging module 2 isperformed by the resonance frequency.

Meanwhile, secondary-side non-contact charging module 2 includessecondary-side coil 11 b, magnetic sheet 4, resonance capacitor (notillustrated), rectifying circuit 6, and power output section 7.Secondary-side coil 11 b receives the magnetic field generated fromprimary-side coil 11 a, converts the magnetic field into a predeterminedcurrent by the electromagnetic induction action, and outputs thepredetermined current to the outside of secondary-side non-contactcharging module 2 through rectifying circuit 6 and power output section7. Rectifying circuit 6 rectifies the predetermined current which is analternating current and converts the predetermined current into apredetermined current which is a direct current (direct current 5 V, 1.5A). Power output section 7 is an external output section ofsecondary-side non-contact charging module 2 and supplies power toelectronic apparatus 200 connected to secondary-side non-contactcharging module 2 through power output section 7.

Next, the case where primary-side non-contact charging module 1 ismounted to a non-contact charger will be described.

FIG. 2 is a diagram illustrating the configuration of a non-contactcharger according to the embodiment of the present invention. An innerportion of the non-contact charger illustrated in FIG. 2 can be viewed.

Non-contact charger 400 that transmits power using the electromagneticinduction action has primary-side non-contact charging module 1 in acase constituting an exterior package.

Non-contact charger 400 has plug 401 that is plugged into outlet 301 ofcommercial power supply 300 disposed indoors or outdoors. By pluggingplug 401 into outlet 301, non-contact charger 400 can receive power fromcommercial power supply 300.

Non-contact charger 400 is disposed on desk 501 and primary-sidenon-contact charging module 1 is disposed in the vicinity of surface 402of the side opposite to the side of a desk surface of non-contactcharger 400. A principal surface of primary-side coil 11 a inprimary-side non-contact charging module 1 is disposed in parallel tosurface 402 of the side opposite to the side of the desk surface ofnon-contact charger 400. In this way, a power reception work area of theelectronic apparatus mounted with secondary-side non-contact chargingmodule 2 can be secured. Non-contact charger 400 may be disposed on awall surface. In this case, non-contact charger 400 is disposed in thevicinity of a surface of the side opposite to the side of the wallsurface.

Primary-side non-contact charging module 1 may have magnet 30 a that isused in aligning with secondary-side non-contact charging module 2. Inthis case, magnet 30 a is disposed in a hollow portion that ispositioned at a center area of primary-side coil 11 a.

Next, primary-side non-contact charging module 1 will be described.

FIG. 3 is a diagram illustrating the primary-side non-contact chargingmodule according to the embodiment of the present invention andillustrating the case where the primary-side coil is circular. ThoughFIG. 3 illustrates the primary-side coil that is a circular coil that iswound in a circular shape, the primary-side coil may be a rectangularcoil that is wound in a substantially rectangular shape. The specificconfiguration of the primary-side non-contact charging module describedhereinafter is basically applied to the secondary-side non-contactcharging module. The difference of the primary-side non-contact chargingmodule and the secondary-side non-contact charging module will bedescribed in detail below.

Primary-side non-contact charging module 1 includes primary-side coil 11a where electrical lines are wound in a spiral shape and magnetic sheet3 that is provided to face a surface of primary-side coil 11 a.

As illustrated in FIG. 3, primary-side coil 11 a includes a coil that iswound around a conductor in a radial direction to draw a whirlpool onthe surface and terminals 22 a and 23 a that function as currentsupplying sections provided on both ends of the coil. That is, terminals22 a and 23 a that function as the current supplying sections suppliesthe current from commercial power supply 300 which is the external powersupply to primary-side coil 11 a. The coil is obtained by windingelectrical lines in parallel on the plane and a surface that is formedby the coil is called a coil surface. The thickness direction is a stackdirection of primary-side coil 11 a and magnetic sheet 3.

Magnetic sheet 3 includes flat portion 31 a that places primary-sidecoil 11 a, center portion 32 a that is a center portion of flat portion31 a and corresponds to a hollow area of primary-side coil 11 a, andlinear concave portion 33 a that inserts a part of a leading line ofprimary-side coil 11 a. In center portion 32 a, a concave portion or athrough-hole is formed with respect to flat portion 31 a.

In primary-side non-contact charging module 1 according to the presentembodiment, primary-side coil 11 a is wound from an inner diameter wherea diameter is 20 mm to the outside and an outer diameter of theprimary-side coil becomes 30 mm. That is, primary-side coil 11 a iswound in a doughnut shape. Primary-side coil 11 a may be wound in acircular shape and may be wound in a polygonal shape.

By wounding the electrical lines to leave a space, the floating capacitybetween the electrical line of an upper stage and the electrical line ofa lower stage decreases and alternating-current resistance ofprimary-side coil 11 a can be suppressed to a minimum. In addition, thethickness of primary-side coil 11 a can be suppressed by wounding theelectrical lines densely.

Primary-side non-contact charging module 1 may have magnet 30 a that isused in aligning with secondary-side non-contact charging module 2. Inthis case, a shape of magnet 30 a is defined to a circular shape and adiameter thereof is defined to 15.5 mm or less by the standard (WPC).Magnet 30 a has a coin shape and needs to be disposed such that a centerthereof is matched with a winding center axis of primary-side coil 11 a.This is to decrease an influence of magnet 30 a with respect toprimary-side coil 11 a.

That is, as an aligning method, the following methods are used. Forexample, a method in which a convex portion is formed in a chargingsurface of a charger, a concave portion is formed in an electronicapparatus of the secondary side, the convex portion is fitted into theconcave portion, and compulsory aligning is physically (geometrically)performed is used. A method in which a magnet is mounted to at least oneof the primary side and the secondary side, the magnets of both sides orone magnet and the other magnetic sheet attract each other, and aligningis performed is used. A method in which the primary side detects theposition of a coil of the secondary side to automatically move a coil ofthe primary side to the position of the coil of the secondary side isused. A method in which a plurality of coils are provided in a chargersuch that a portable apparatus is chargeable in all places of a chargingsurface of the charger is used.

As such, the various methods that are used in aligning the coils of theprimary-side (charging-side) non-contact charging module and thesecondary-side (charged-side) non-contact charging module are described.However, the methods are divided into methods performed with the magnetand methods performed without the magnet. In addition, according to theprimary-side (charging-side) non-contact charging module, theprimary-side non-contact charging module is configured to be adapted toboth of the secondary-side (charged-side) non-contact charging modulewith the magnet and the secondary-side (charged-side) non-contactcharging module without the magnet, and charging can be performed,regardless of a type of the secondary-side (charged-side) non-contactcharging module. Therefore, convenience is improved. Likewise, accordingto the secondary-side (charged-side) non-contact charging module, thesecondary-side non-contact charging module is configured to be adaptedto both of the primary-side (charging-side) non-contact charging modulewith the magnet and using the magnet in aligning and the primary-side(charging-side) non-contact charging module without the magnet and notusing the magnet in aligning, and charging can be performed, regardlessof a type of the primary-side (charging-side) non-contact chargingmodule. Therefore, convenience is improved. That is, in the non-contactcharging module that performs power transmission by the electromagneticinduction action with the other non-contact charging module which is acounterpart performing the power transmission and performs aligningusing the magnet included in the other non-contact charging module orperforms aligning without using the magnet when aligning with the othernon-contact charging module is performed, the non-contact chargingmodule needs to be configured to surely perform the power transmission.

As a first method that disposes magnet 30 a in the case whereprimary-side non-contact charging module 1 has magnet 30 a, a methodthat disposes magnet 30 a on a top surface of center portion 32 a ofmagnetic sheet 3 is known. As a second method that disposes magnet 30 a,a method that disposes magnet 30 a at the position instead of centerportion 32 a of magnetic sheet 3 is known. In the second method, sincemagnet 30 a is disposed in the hollow area of the coil, a size ofprimary-side non-contact charging module 1 can be decreased.

When the magnet is not used in aligning of primary-side non-contactcharging module 1 and secondary-side non-contact charging module 2, themagnet 30 a illustrated in FIG. 3 is not needed.

In this case, an influence of the magnet with respect to powertransmission efficiency of the non-contact charging module will bedescribed. In general, the magnet is provided in the hollow portion ofthe coil incorporated in at least one of the primary-side non-contactcharging module and the secondary-side non-contact charging module.Thereby, the magnet and the magnet or the magnet and the magnetic sheet3 can be placed closely each other as close as possible, and, at thesame time, the primary-side coil and the secondary-side coil can beplaced closely each other. The magnet is circular. In this case, thediameter of the magnet becomes smaller than the inner width of the coil.In the present embodiment, the diameter of the magnet is about 15.5 mm(about 10 to 20 mm) and the thickness thereof is about 1.5 to 2 mm. Aneodymium magnet may be used and the strength thereof may be about 75 to150 mT. In the present embodiment, since an interval of the coil of theprimary-side non-contact charging module and the coil of thesecondary-side non-contact charging module is about 2 to 5 mm,sufficient aligning can be performed by the corresponding magnet.

When the magnetic flux is generated between the primary-side coil andthe secondary-side coil to transmit power, if the magnet exists betweenthe primary-side coil and the secondary-side coil and around theprimary-side coil and the secondary-side coil, the magnetic flux extendsto avoid the magnet. The magnetic flux that passes through the magnetbecomes an eddy current or generates heat in the magnet and is lost. Ifthe magnet is disposed in the vicinity of the magnetic sheet, thepermeability of the magnetic sheet in the vicinity of the magnet may bedecreased. Therefore, magnet 30 a that is included in primary-sidenon-contact charging module 1 may decrease the L values of bothprimary-side coil 11 a and secondary-side coil 11 b. As a result,transmission efficiency between the non-contact charging modules may bedecreased.

FIGS. 4A, 4B, 4C and 4D are a detailed diagram illustrating theprimary-side non-contact charging module according to the embodiment ofthe present invention. FIG. 4A is a top view of the primary-sidenon-contact charging module and FIG. 4B is a cross-sectional view takenalong the line A-A of the primary-side non-contact charging module inFIG. 4A. FIG. 4C is a cross-sectional view taken along the line B-B ofthe primary-side non-contact charging module in FIG. 4A in the casewhere a linear concave portion is provided. FIG. 4D is a cross-sectionalview taken along the line B-B of the primary-side non-contact chargingmodule in FIG. 4A in the case where a slit is provided. FIGS. 4A and 4Billustrate the case where magnet 30 a is not included. When the magnetis included, magnet 30 a illustrated by a dotted line is included.

Primary-side coil 11 a achieves decreasing the thickness of non-contactcharger 400 mounted with primary-side non-contact charging module 1. Forthis reason, an area from a winding starting portion positioned in acenter area of primary-side coil 11 a to terminal 23 a is configured astwo stages in the thickness direction and the remaining area isconfigured as one stage. At this time, the electrical line of the upperstage and the electrical line of the lower stage are wound to leave aspace, the floating capacity between the electrical line of the upperstage and the electrical line of the lower stage decreases, and thealternating-current resistance of primary-side coil 11 a can besuppressed to a minimum.

When the electrical lines are stacked and primary-side coil 11 a isextended in the thickness direction of primary-side non-contact chargingmodule 1, the amount of current that flows to primary-side coil 11 a canbe increased by increasing the winding number of primary-side coil 11 a.When the electrical lines are stacked, if the electrical line of theupper stage and the electrical line of the lower stage are wounddensely, the thickness of primary-side coil 11 a is suppressed, and theamount of current flowing to primary-side coil 11 a can be increased.

In the present embodiment, primary-side coil 11 a is formed using theelectrical lines having a circular cross-sectional shape. However, theelectrical lines that have a rectangular cross-sectional shape may beused. When the electrical lines having the circular cross-sectionalshape are used, gaps are generated between the electrical lines adjacentto each other. For this reason, the floating capacity between theelectrical lines decreases and the alternating-current resistance ofprimary-side coil 11 a can be suppressed to a minimum.

It is preferable to wind primary-side coil 11 a in one stage in thethickness direction, instead of winding primary-side coil 11 a in twostages in the thickness direction, because the alternating-currentresistance of primary-side coil 11 a decreases and transmissionefficiency can be increased. This is because the floating capacity isgenerated between the electrical line of the upper stage and theelectrical line of the lower stage, if the electrical lines are wound inthe two stages. Therefore, it is preferable to wind most of the parts ofprimary-side coil 11 a in one stage, instead of winding all of the partsof primary-side coil 11 a in two stages. By winding primary-side coil 11a in one stage, primary-side non-contact charging module 1 can be formedto have the small thickness. When a planar coil portion is configured bythe two electrical lines, the two electrical lines are electricallyconnected by solder in portions of terminals 22 a and 23 a. For thisreason, the two electrical lines may be configured as one thickelectrical line. The two electrical lines may be wound in parallel tothe coil surface and may be wound vertically to the coil surface. Thatis, when the two electrical lines are parallel to the coil surface, thetwo electrical lines are wound around the same center in a planar shapeand one electrical line is inserted into the other electrical line inthe radial direction. As such, the two electrical lines are bonded inthe portions of terminals 22 a and 23 a to function as one electricalline, and the thickness can be suppressed even though the electricallines have the same cross-sectional area. That is, the cross-sectionalarea of the electrical line where the diameter is 0.25 mm can beobtained by preparing two electrical lines where the diameter is 0.18mm. Therefore, if one electrical line where the diameter is 0.25 mm isprepared, the thickness of one turn of the coil is 0.25 mm and the widthof the coil in the radial direction is 0.25 mm. However, if twoelectrical lines where the diameter is 0.18 mm are prepared, thethickness of one turn of the coil is 0.18 mm and the width of the coilin the radial direction is 0.36 mm. The thickness direction is a stackdirection of the planar coil portion and magnetic sheet 3. Only parts ofthe center side of the coil may overlap in two stages in the thicknessdirection and the remaining part of the outside may be configured as onestage. In the case where the electrical lines are wound vertically tothe coil surface, the thickness of primary-side non-contact chargingmodule 1 increases. However, the cross-sectional area of the electricalline increase substantially, the amount of current that flows to theplanar coil portion can be increased, and the sufficient winding numbercan be easily secured. In the present embodiment, primary-side coil 11 ais configured by the electrical lines having the diameter of about 0.18to 0.35 mm. In primary-side coil 11 a of primary-side non-contactcharging module 1, the electrical lines having the diameter of 0.25 to0.35 mm are preferable.

The loss in primary-side coil 11 a can be prevented by decreasing thealternating-current resistance of primary-side coil 11 a and powertransmission efficiency of primary-side non-contact charging module 1that depends on the L value can be improved by improving the L value.

In the present embodiment, primary-side coil 11 a is formed in anannular shape (circular shape). A shape of primary-side coil 11 a is notlimited to the annular shape (circular shape) and may be an ellipticalshape, a rectangular shape, and a polygonal shape. If aligning ofprimary-side non-contact charging module 1 and secondary-sidenon-contact charging module 2 is considered, the shape of primary-sidecoil 11 a is preferably the annular shape (circular shape). This reasonis as follows. When the shape of primary-side coil 11 a is the annularshape (circular shape), because transmission/reception of power can beperformed over a wider range, aligning of primary-side coil 11 a ofprimary-side non-contact charging module 1 and secondary-side coil 11 bof secondary-side non-contact charging module 2 can be easily performed.That is, since transmission/reception of the power can be performed overa wider range, it is difficult that secondary-side non-contact chargingmodule 2 receives an influence of an angle with respect to primary-sidenon-contact charging module 1.

Terminals 22 a and 23 a may be placed closely each other and may beapart from each other. However, when terminals 22 a and 23 a are apartfrom each other, primary-side non-contact charging module 1 may beeasily mounted.

Magnetic sheet 3 is provided to improve power transmission efficiency ofnon-contact charging using the electromagnetic induction action, andincludes flat portion 31 a, center portion 32 a that is a center andcorresponds to an inner diameter of primary-side coil 11 a, and linearconcave portion 33 a. When magnet 30 a is provided to perform aligningof primary-side non-contact charging module 1 and secondary-sidenon-contact charging module 2, magnet 30 a may be disposed on centerportion 32 a and may be disposed at the position instead of centerportion 32 a. A concave portion or a through-hole may be provided in aportion that corresponds to the hollow portion of coil 11 a of magneticsheet 3. In addition, the linear concave portion 33 a can be replacedslit 34 a in FIG. 4D.

As magnetic sheet 3, a ferrite sheet of the Ni—Zn system, a ferritesheet of the Mn—Zn system, and a ferrite sheet of the Mg—Zn system andthe like may be used. Magnetic sheet 3 may be configured as a singlelayer, may be configured by stacking a plurality of sheets made of thesame material in the thickness direction, and may be configured bystacking a plurality of different magnetic sheets in the thicknessdirection. Magnetic sheet 3 is preferably configured such that thepermeability is 250 or more and the saturation magnetic flux density is350 mT or more.

An amorphous metal may be used as magnetic sheet 3. When the ferritesheet is used as magnetic sheet 3, the alternating-current resistance ofprimary-side coil 11 a can be decreased, and when the amorphous metal isused as magnetic sheet, the thickness of primary-side coil 11 a can bedecreased. The shape of magnetic sheet 3 may be a circular shape, arectangular shape, a polygonal shape, and a rectangular shape and apolygonal shape having large curved lines at four corners.

Next, an influence of the magnet with respect to primary-sidenon-contact charging module 1 and secondary-side non-contact chargingmodule 2 (described later) below will be described. The magnetic fieldthat is generated by primary-side non-contact charging module 1 isreceived by secondary-side coil 11 b in secondary-side non-contactcharging module 2 to transmit power. In this case, if the magnet isdisposed around primary-side coil 11 a and secondary-side coil 11 b, themagnetic field may be generated to avoid the magnet or the magneticfield that passes through the magnet may be removed. The permeability ofa part of magnetic sheet 3 that is close to the magnet may decrease.That is, the magnetic field is weakened by the magnet. Therefore, inorder to minimize the magnetic field weakened by the magnet, acountermeasure is necessary for primary-side coil 11 a andsecondary-side coil 11 b to be apart from the magnet or magnetic sheet 3that is difficult to be affected by the magnet.

Next, the case where secondary-side non-contact charging module 2 ismounted to a portable terminal apparatus will be described.

FIG. 5 is a diagram illustrating the configuration of a portableterminal apparatus according to the embodiment of the present inventionand is a perspective view illustrating the exploded portable terminalapparatus.

Portable terminal apparatus 520 includes liquid crystal panel 521,operation button 522, substrate 523, battery pack 524 and the like.Portable terminal apparatus 520 that receives power using theelectromagnetic induction action is a portable terminal apparatus thatincludes secondary-side non-contact charging module 2 in casing 525 andcasing 526 forming an exterior package thereof.

On a back surface of casing 525 where liquid crystal panel 521 andoperation button 522 are provided, substrate 523 including a controlsection that receives information input from operation button 522,displays needed information on liquid crystal panel 521, and controlsentire portable terminal apparatus 520 is provided. In addition, on theback surface of substrate 523, battery pack 524 is provided. Batterypack 524 is connected to substrate 523 and supplies power to substrate523.

On the back surface of battery pack 524, that is, on the side of casing526, secondary-side non-contact charging module 2 is provided.Secondary-side non-contact charging module 2 receives power fromprimary-side non-contact charging module 1 by the electromagneticinduction action and charges battery pack 524 using the power.

Secondary-side non-contact charging module 2 includes secondary-sidecoil 11 b, magnetic sheet 4 and the like. When a power supply directionis set to the side of casing 526, if secondary-side coil 11 b andmagnetic sheet 4 are disposed sequentially from the side of casing 526between casing 526 and substrate 523, an influence of substrate 523 andbattery pack 524 can be alleviated and power can be received. AlthoughFIG. 5 illustrates a state in which magnetic sheet 4 is disposed closerto the side of casing 526 than secondary-side coil 11 b, FIG. 5schematically illustrates the configuration for easy understanding. Inpractice, as described above, secondary-side coil 11 b and magneticsheet 4 are disposed sequentially from the side of casing 526.

Next, secondary-side non-contact charging module 2 will be described.

FIG. 6 is a diagram illustrating the secondary-side non-contact chargingmodule according to the embodiment of the present invention andillustrating the case where the secondary-side coil is a circular coil.

FIGS. 7A, 7B, 7C and 7D are a detailed diagram illustrating thesecondary-side non-contact charging module according to the embodimentof the present invention. FIG. 7A is a top view of the secondary-sidenon-contact charging module and FIG. 7B is a cross-sectional view takenalong the line C-C of the secondary-side non-contact charging module inFIG. 7A. FIG. 7A is a cross-sectional view taken along the line D-D ofthe secondary-side non-contact charging module in FIG. 7A in the casewhere a linear concave portion is provided. FIG. 7D is a cross-sectionalview taken along the line D-D of the secondary-side non-contact chargingmodule in FIG. 7A in the case where a slit is provided. FIGS. 7A and 7Billustrate the case where magnet 30 b is not included. In the case wherethe magnet is included, magnet 30 b that is illustrated by a dotted lineis included.

FIGS. 6 and 7 that illustrate secondary-side non-contact charging module2 correspond to FIGS. 3 and 4 that illustrate primary-side non-contactcharging module 1. The configuration of secondary-side non-contactcharging module 2 is substantially the same as the configuration ofprimary-side non-contact charging module 1.

Secondary-side non-contact charging module 2 is different fromprimary-side non-contact charging module 1 in the size and the materialof magnetic sheet 4. Magnetic sheet 4 that is used in secondary-sidenon-contact charging module 2 has the size that is smaller than about40×40 mm and the thickness that is about 2 mm or less.

The size of magnetic sheet 3 that is used in primary-side non-contactcharging module 1 is different from the size of magnetic sheet 4 that isused in secondary-side non-contact charging module 2. This is becausesecondary-side non-contact charging module 2 is generally mounted to aportable electronic apparatus and a small size is required. In thepresent embodiment, magnetic sheet 4 is substantially square and has thesize of about 33×33 mm. It is demanded to form magnetic sheet 4 with thesize equal to or larger than the size of an outer circumferential end ofsecondary-side coil 11 b. The shape of magnetic sheet 4 may be acircular shape, a rectangular shape, a polygonal shape, and arectangular shape and a polygonal shape having large curved lines atfour corners.

Since secondary-side non-contact charging module 2 is used in a portableterminal as the reception side of power supply, an occupation space ofsecondary-side non-contact charging module 2 in the portable terminalhas no room. Since the amount of current flowing to secondary-side coil11 b of secondary-side non-contact charging module 2 is small, aninsulating property of magnetic sheet 4 is not so required. In thepresent embodiment, secondary-side coil 11 b is configured using theelectrical lines having the diameter of about 0.18 to 0.35 mm and theelectrical lines having the diameter of about 0.18 to 0.30 mm arepreferable in secondary-side coil 11 b of secondary-side non-contactcharging module 2.

When the mounted electronic apparatus is a mobile phone, thesecondary-side non-contact charging module is generally disposed betweenthe case constituting the exterior package of the mobile phone and thebattery packet positioned in the mobile phone. In general, since thebattery pack is a casing made of aluminum, the battery pack adverselyaffects power transmission. This is because the eddy current isgenerated in the aluminum in a direction weakening the magnetic fluxgenerated by the coil and the magnetic flux of the coil is weakened. Forthis reason, an influence with respect to the aluminum needs to bealleviated by providing magnetic sheet 4 between the aluminum which isthe exterior package of the battery pack and secondary-side coil 11 bdisposed on the exterior package thereof.

Next, the thickness of the center portions of magnetic sheets 3 and 4will be described.

FIGS. 8A, 8B, 8C and 8D are a conceptual diagram of a magnetic sheet ofa non-contact charging module according to the embodiment of the presentinvention. For example, magnetic sheet 4 that is included insecondary-side non-contact charging module 2 is used. FIG. 8A is a topview of the magnetic sheet of the non-contact charging module accordingto the embodiment of the present invention and FIG. 8B is a top view ofthe magnetic sheet in the case where the position of the linear concaveportion of the magnetic sheet in FIG. 8A is changed. In this case, ahole portion that is configured as a concave portion or a through-holeis provided in center portion 32 b. FIG. 8C is a cross-sectional viewtaken along the line E-E of FIG. 8A, FIG. 8D is a cross-sectional viewtaken along the line F-F of FIG. 8A in the case where the center portionis configured as the concave portion, and FIG. 8E is a cross-sectionalview taken along the line F-F of FIG. 8A in the case where the centerportion is configured as the through-hole. In center portion 32 b, theconcave portion or the through-hole is provided.

By providing the hole portion configured as the concave portion or thethrough-hole in center portion 32 b, an influence of magnet 30 a that isincluded in primary-side non-contact charging module 1 can be decreased.The reason will be described below.

For example, primary-side non-contact charging module 1 including magnet30 a and magnetic sheet 4 of secondary-side non-contact charging module2 performing power transmission will be described. However, thedescription of magnetic sheet 4 of secondary-side non-contact chargingmodule 2 as described below is applied to secondary-side non-contactcharging module 2 including magnet 30 b and magnetic sheet 3 ofprimary-side non-contact charging module 1 performing powertransmission. That is, a center portion of the magnetic sheet of thenon-contact charging module that can perform aligning and powertransmission in both of the case where the other non-contact chargingmodule which is the counterpart of the power transmission includes themagnet and the case where the other non-contact charging module does notinclude the magnet will be described.

As described above, the non-contact power transmitting apparatus may usethe magnet or may not use the magnet in aligning of primary-sidenon-contact charging module 1 and secondary-side non-contact chargingmodule 2. The magnetic flux between the primary-side and thesecondary-side non-contact charging modules may be disturbed when themagnet exists. For this reason, the L values of primary-side coil 11 aof primary-side non-contact charging module 1 and secondary-side coil 11b of secondary-side non-contact charging module 2 greatly decrease whenthe magnet exists.

Primary-side coil 11 a forms an LC resonance circuit with a resonancecapacitor, in primary-side non-contact charging module 1. At this time,if the L values greatly change in the case where magnet 30 a is used inaligning and the case where magnet 30 a is not used in aligning, theresonance frequency with the resonance capacitor may greatly change. Theresonance frequency is used in power transmission of primary-sidenon-contact charging module 1 and secondary-side non-contact chargingmodule 2. For this reason, if the resonance frequency greatly changesaccording to existence or non-existence of magnet 30 a, powertransmission may not be correctly performed.

Therefore, in order to make the resonance frequency in the case wheremagnet 30 a is used in aligning similar to the resonance frequency inthe case where magnet 30 a is not used, the L value of secondary-sidecoil 11 b in the case where magnet 30 a is used in aligning and the Lvalue of secondary-side coil 11 b in the case where magnet 30 a is notused in aligning need to be set to similar values.

Next, a relation of the thickness of the center portion of magneticsheet 4 and the L value of secondary-side coil 11 b in the case whereprimary-side non-contact charging module 1 is included and the casewhere primary-side non-contact charging module 30 a is not included willbe described.

FIG. 9 is a diagram illustrating a relation of an L value of a coil ofthe non-contact charging module and the thickness of a center portion inthe case where a magnet is used and in the case where the magnet is notused in aligning in the other non-contact charging module according tothe embodiment of the present invention. As the degree of a hollow, 0%illustrates a state in which center portion 32 b is not configured asthe concave portion and is flat, and 100% illustrates a state in whichcenter portion 32 b is configured as the through-hole.

In the case where magnet 30 a is not used, as the thickness of centerportion 32 b of magnetic sheet 4 decreases, the magnetic field ofsecondary-side coil 11 b decreases and the L value decreases. Meanwhile,in the case where magnet 30 a is used, as the thickness of centerportion 32 b of magnetic sheet 4 decreases, the distance of a stackdirection of magnetic sheet 4 and magnet 30 a increases. For thisreason, an influence of magnet 30 a decreases, the magnetic field ofsecondary-side coil 11 b increases, and the L value increases. In thecase where center portion 32 b is configured as the through-hole, the Lvalues are most similar. That is, if center portion 32 b is configuredas the through-hole, an influence of magnet 30 a that is used inaligning can be suppressed to a minimum.

Since magnet 30 a and magnetic sheet 4 attract each other and performaligning, aligning precision is improved when center portion 32 b hassome thickness. In particular, aligning precision can be stabilized bysetting the hollow degree to 60% or less.

Therefore, if the hollow degree is set to 40 to 60%, the L values ofsecondary-side coil 11 b in the case where magnet 30 a is used inaligning and the case where magnet 30 a is not used in aligning can beset to be similar to each other and an aligning effect of magnet 30 acan be sufficiently obtained. That is, magnet 30 a and center portion 32b of magnetic sheet 4 attract each other and the centers thereof can bealigned.

In the present embodiment, the hollow degree is set to about 50% and theeffects of both sides can be obtained. In order to maintain about halfof the entire thickness, the through-hole may be filled with themagnetic material up to half the entire depth, after the through-hole isformed. The hole portion (concave portion or through-hole) that isprovided in center portion 32 b does not need to have the shape and thesize equal to those of center portion 32 a. Even though the shape ofcenter portion 32 b, that is, the hollow portion of the coil is asubstantially rectangular shape or a substantially circular shape, thehole portion may have various shapes without depending on the shapethereof. That is, the hole portion may have a rectangular shape or acircular shape. The hole portion is preferably formed to be smaller thancenter portion 32 b and may secure an area of 30% or more of an area ofcenter portion 32 b.

Since magnetic sheets 3 and 4 may be formed by stacking a materialhaving the high saturation magnetic flux density and a material havingthe high permeability, the center portion of the material having thehigh saturation magnetic flux density may be formed to be flat, thethrough-hole may be formed in the center portion of the material havingthe high permeability, and center portions 32 a of magnetic sheets 3 and4 may be formed in a concave shape. The material having the highsaturation magnetic flux density means a magnetic sheet that has thesaturation magnetic flux density higher than that of the material havingthe high permeability and has the permeability lower than that of thematerial having the high permeability, and may be a ferrite sheet inparticular.

The diameter of the concave portion and the through-hole may be smallerthan the inner diameter of secondary-side coil 11 b. By setting thediameter of the concave portion or the through-hole to be substantiallyequal to the inner diameter of secondary-side coil 11 b (smaller thanthe inner diameter of the coil by 0 to 2 mm), the magnetic field in aninner circumferential circle of secondary-side coil 11 b can beincreased.

By setting the diameter of the concave portion or the through-hole to besmaller to the inner diameter of the coil (smaller than the innerdiameter of the coil by 2 to 8 mm) to become a stepped shape, thestepped outer side can be used in aligning and the inner side can beused to make the L values of primary-side coil 11 a in the case wheremagnet 30 a is used in aligning and the case where magnet 30 a is notused in aligning similar to each other. The size of the concave portionor the through-hole may be larger than the size of magnet 30 a. That is,the hole portion may be formed to have the diameter larger than that ofmagnet 30 a and have the size smaller than that of the hollow portion ofsecondary-side coil 11 b.

By setting the shape of the top surface of the concave portion or thethrough-hole to be equal to the shape of the hollow portion ofsecondary-side coil 11 b, magnet 30 a and center portion 32 b ofmagnetic sheet 4 can attract with a good balance and the centers thereofcan be precisely aligned.

By configuring all of the ends of the concave portion or thethrough-hole to have the same distance from the inner diameter ofsecondary-side coil 11 b, magnet 30 a and center portion 32 b ofmagnetic sheet 4 can attract with a good balance and the centers thereofcan be precisely aligned.

By matching the center of the shape of the top surface of the concaveportion or the through-hole with the center of the hollow portion ofsecondary-side coil 11 b, magnet 30 a and center portion 32 b ofmagnetic sheet 4 can attract with a good balance and the centers thereofcan be precisely aligned. By forming the concave portion or thethrough-hole to be bigger than magnet 30 a, an influence of magnet 30 acan be suppressed with a good balance.

As described above, the configuration where the center portion isconfigured as the hole portion can be applied to the primary-sidenon-contact charging and magnetic sheet 3 and the effect is obtainedeven though the hole portion is included in center portion 32 a ofmagnetic sheet 3 of primary-side non-contact charging module 1. That is,primary-side non-contact charging module 1 that can perform aligning andeffective power transmission in both of the case where secondary-sidenon-contact charging module 2 includes magnet 30 b and the case wheresecondary-side non-contact charging module 2 does not include magnet 30b can be configured.

Thick portions may be formed in areas where coils 11 a and 11 b on flatportions 31 a and 31 b are not disposed, in the four corners of magneticsheets 3 and 4. That is, none are placed on magnetic sheets 3 and 4corresponding to portions that are closer to the outside than the outercircumference of coils 11 a and 11 b on flat portions 31 a and 31 b inthe four corners of magnet sheets 3 and 4. Therefore, by increasing thethickness of magnetic sheets 3 and 4 by forming the thick portions inthe areas, power transmission efficiency of the non-contact powertransmitting apparatus can be improved. The thickness of the thickportions is preferably large. However, the thickness of the thickportions is set to be almost equal to the thickness of the electricallines to decrease the thickness of the apparatus.

FIGS. 10A and 10B are a top view of the non-contact charging modulewhere coil 11 b is wound in a rectangular shape or a circular shape.FIG. 10A illustrates the case where coil 11 b is wound in therectangular shape and FIG. 10B illustrates the case where coil 11 b iswound in the circular shape. Even when coil 11 b is wound in therectangular shape or the circular shape, the concave portion or thethrough-hole is formed in the hollow portion of coil 11 b and theabove-described effect is obtained by the hole portion. In FIGS. 10A and10B, the secondary-side non-contact charging module is illustrated.However, the primary-side non-contact charging module may have the sameeffect.

Industrial Applicability

According to the non-contact charging module according to the presentinvention, the change of the L value of the coil that is provided in thenon-contact charging module can be suppressed in both of the case wherethe magnet of the counterpart-side non-contact charging module is usedin aligning of the primary-side non-contact charging module and thesecondary-side non-contact charging module and the case where the magnetis not used. Therefore, the non-contact charging module can be used inboth of the case where the magnet is used and the case where the magnetis not used and can be used as a reception-side charging apparatus whena portable terminal such as a mobile phone, a portable audio device, anda portable computer and a portable apparatus such as a digital cameraand a video camera are charged.

REFERENCE SIGNS LIST

-   1 Primary-side non-contact charging module-   2 Secondary-side non-contact charging module-   3 Magnetic sheet (primary side)-   4 Magnetic sheet (secondary side)-   11 a Primary-side coil-   11 b Secondary-side coil-   22 a, 23 a Terminal (primary side)-   22 b, 23 b Terminal (secondary side)-   30 a Magnet (primary side)-   30 b Magnet (secondary side)-   31 a Flat portion (primary side)-   31 b Flat portion (secondary side)-   32 a Center portion (primary side)-   32 b Center portion (secondary side)-   33 a Linear concave portion (primary side)-   33 b Linear concave portion (secondary side)-   34 a Slit (primary side)-   34 b Slit (secondary side)

1. A non-contact charging module that performs power transmission withanother non-contact charging module, the non-contact charging modulecomprising: a planar coil in which a conducting wire is wound; and amagnetic sheet that places the planar coil, wherein the magnetic sheethas a hole provided within an inner winding of the planar coil.
 2. Thenon-contact charging module according to claim 1, wherein thenon-contact charging module has a case where a magnet included within aninner winding of the planar coil in another non-contact charging moduleis used to align with the non-contact charging module or a case wherethe magnet is not used to align with the transmission-side non-contactcharging module.
 3. The non-contact charging module according to claim1, wherein the hole is a through-hole.
 4. The non-contact chargingmodule according to claim 1, wherein the hole is a concavity.
 5. Thenon-contact charging module according to claim 4, wherein the depth ofthe concavity is 40 to 60% of a thickness of the magnetic sheet.
 6. Thenon-contact charging module according to claim 1, wherein a shape of atop surface of the hole is the same as a shape of the inner winding ofthe planar coil.
 7. The non-contact charging module according to claim1, wherein all ends of the hole are at the same distance from the innerwinding of the planar coil.
 8. The non-contact charging module accordingto claim 1, wherein an area of the hole is equal to or more than 30% ofan area of the inner winding of the planar coil.
 9. The non-contactcharging module according to claim 1, wherein the hole is formed largerthan the magnet.
 10. The non-contact charging module according to claim1, wherein a center of the hole coincides with a center of the innerwinding of the planar coil.
 11. The non-contact charging moduleaccording to claim 1, wherein the inner winding of the planar coil is ina substantially rectangular shape.
 12. The non-contact charging moduleaccording to claim 1, wherein the conducting wire is wound in asubstantially rectangular shape in the planar coil
 13. The non-contactcharging module according to claim 1, wherein the planar coil is formedby spirally winding the conducting wire.
 14. The non-contact chargingmodule according to claim 1, further comprising an alignment module,wherein the alignment module does not use a magnet to align the othernon-contact charging module with the non-contact charging module. 15.The non-contact charging module according to claim 1, wherein themagnetic sheet touches the coil.
 16. The non-contact charging moduleaccording to claim 2, wherein both first L value which is the L value ofthe planar coil when a magnet is included within an inner winding of theplanar coil in another non-contact charging module and second L valuewhich is the L value of the planar coil when a magnet isn't includedwithin an inner winding of the planar coil in another non-contactcharging module are between third L value and fourth L value, the thirdL value is the L value of a planar coil which is placed on a magneticsheet which doesn't have a hole provided within an inner winding of theplanar coil when a magnet is included within an inner winding of theplanar coil in another non-contact charging module, and the fourth Lvalue is the L value of a planar coil which is placed on a magneticsheet which doesn't have a hole provided within an inner winding of theplanar coil when a magnet isn't included within an inner winding of theplanar coil in another non-contact charging module.
 17. A reception-sidenon-contact charging apparatus, comprising the non-contact chargingmodule according claim 1, that receives power from a transmission-sidenon-contact charging apparatus.
 18. A transmission-side non-contactcharging apparatus comprising the non-contact charging module accordingto claim 1, that transmits power to a reception-side non-contactcharging apparatus.